In 1841, President William Henry Harrison died of pneumonia after serving for one month. He was the ninth U.S. president and the first to die in office. He was succeeded by Vice President John Tyler, first person to occupy the office without being elected to it.

In 1887, Susanna Medora Salter was elected as the first woman mayor in the United States, serving for one year as head of the municipal government of Argonia, Kan.

In 1896, the Yukon gold rush began with the announcement of a strike in the Northwest Territory of Canada.

In 1949, representatives of 12 nations gathered in Washington, D.C., to sign the North Atlantic Treaty, creating the NATO alliance.

In 1968, civil rights leader Martin Luther King Jr. was assassinated in Memphis.

In 1969, CBS canceled "The Smothers Brothers." The popular hour-long comedy series had often been at odds with network censors.

In 1983, the space shuttle Challenger lifted off on its inaugural mission.

In 1991, Sen. John Heinz, R-Pa., and four others were killed when their chartered airplane collided with a helicopter over a schoolyard near Philadelphia.

In 1992, billionaire Sam Moore Walton, founder of Wal-Mart, died of cancer at 74. His retail store chain helped make him one of the world's richest men.

In 1993, President Clinton and Russian President Boris Yeltsin ended their two-day summit in Vancouver, B.C., Canada, with a larger than expected U.S. aid pledge of $1.62 billion.

Also in 1993, ceremonies were held in Atlanta, Martin Luther King Jr.'s birthplace, and in Memphis, the city where he died, to mark the 25th anniversary of the civil rights leader's assassination.

In 1995, a Colorado man was convicted of trying to assassinate President Clinton in Oct. 1994.

In 1999, several NATO countries announced they would take in refugees being forced out of Kosovo by Serbian forces.

In 2000, the Nasdaq plunged 574 points (more than 13 percent) but then rose 500 points in one of the wildest days ever on Wall Street.

In 2001, former Philippine President Joseph Estrada, ousted in January during a popular uprising, was indicted on charges he took millions of dollars in bribes and kickbacks.

In 2002, as Israel stepped up its attacks on Palestinians on the West Bank, President Bush demanded Israelis stop and pull back.

Also in 2003, a published report said U.S. Marines in Iraq were tipped off about POW Jessica Lynch's location, leading to her dramatic April 1 rescue, by an Iraqi lawyer distressed at the way he saw her being treated.

In 2004, three explosions, termed a terrorist attack by the government, killed five people and hurt at least 100 others at a residential housing compound in Rihyadh, Saudi Arabia.

A thought for the day: Plato said, "At the touch of love everyone becomes a poet."

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